When setting up persistent home and/or opt in a USB drive, it is ideal to use the UUID.

To set up persistent opt, edit the bootloader configuration file, adding persistent opt.

If you have installed Tinycore using the installer, you should already have tce=UUID=“9aff3da3-474d-440d-bb6c-3240afe84ac6” (the number will be different). To set up persistent opt, copy the UUID number, like this

If you use backup as well as persistent home and opt, edit /opt/.filetool.lst, delete all references to the home and opt directories (in the version I am using that is everything), then add a list of files and directories you want backed up to /opt/.filetool.lst.